The metropolitan area boasts a system of 181 emergency sirens, which were updated in 2002 in a $4.5 million project replacing Cold War-era sirens that at the time only stretched over the most densely populated areas, the city’s website stated. The coverage area of the new system is nearly four times more than the previous one, which had just 44 sirens.

Another War-era idea the city has begun to replace are public shelters for storm protection. It says that driving to a shelter during extreme weather can pose a greater risk to residents and it notes emergency experts now advising they “shelter in place” when told to take cover.

Although taking shelter underground is preferable during a tornado event, most Oklahoma homes actually don’t have basements or cellars. An Associated Press article published after the deadly May 3, 1999, tornado, to which many are comparing the May 20, 2013, twister, reported that many people aren’t building these underground structures due to cost and soil conditions.